Electrically-controlled power cut-out safety device



G. GALPIN AND D. H. BAER. ELECTRICALLY CONTROLLED POWER CUT-0UT SAFETY DEVICE.

2 SHEETS-SHEET l. mm I in venmm',

APPllcATmN FILED MAY 1s. 1918. BSQ,

IIIIIIIIIIIIIIIIIIII lllhllnlrlnulll Ill.Il

mm i e. GALPN AND D. H.,BAER. ELECTRICALLY CONTROLLED POWER CUT-OUT SAFETY DEVICE.

APPEICATION FILED MAYI8, 191B. Lw. melma 001;. 31, 1922.

2 SHEEIS-SHEE1 2.

Patented @et fdl, i922,

.kan i GEORGE GALPN EAN13 DAVD H. 0F DETROET, MICHIGAL, .ASSIGNQ'RS 'IO MORGAN @t llTlG-HT, A CRPORT'ON 0F MICHGAN.

ELECTRICALLY-GONTEOLLED PD'WER CUT-OUT DET/TCE.

Application filed May 18, 1918. Serial No. 235,304.

Safety Devices, of which the following is a specification. 4 The invention has i'or its object to provide a safety device adapted for a train oi machines, whereby the operator oi any one machine may instantly stop thev tra-in of machinesjin case of accident in the opera tion of any one of them. For example, the

`invention maybe applied to a train 0i crushing, grinding or mixing rolls driven from a common powerfunit. It an accident happens inthe operation of a ma chine, any of the operators will be enabled to instantly stop the' rolls and prevent injury, ory further injury, and this by move'- yment of a lever .on or near each machine.

The apparatus consists of a driving member common to the machine units'and `an l.

electrically Acontrolled driving connection for the said driving member, a switch ele` ment for each machine unit, and a relay,

the switch elements and relay'being in circuit with the electrical control device.

The electrically controlled driving con-y nection'may be an automatic cut-out switch forVv the motor or engine., a clutch or equivalent mechanism for yconnecting and disc0n necting a driving` shait common to the machine units from the source of power, or merely a motor in circuit with the switches andrelay, as in the construction illustrated in the drawings.

ln the embodiment of the invention illus trated in the drawings, a series of ma-` chine units are operatively connected with a common driving shaft, the latter being geared to the motor shaft, the motor shaft being provided with a brake device.` Each machine unit is provided with a switch in circuit' with the source of currentleading` to the motor and 'also in circuit with the onev machine relay. rl'he operator of any switch, shut unit may, by disconnecting his oil1 current to the motor, permit `the engagement'oi thebraketo stop the rotation of the driving shaft, and'also open the relay. The function ot Htherelay is to prevent `ing device D, andthe latter `the circuit is broken through the solenoid.

The invention may be understood by reference to the accompanying drawings, in which:

Fig. l is a front elevation o-'a machine unit provided with. a switch and operating means therefor, and

Fig. 2 is a sectional end view oi the same.

Fig. 3 is a detail sectional view illustrating a frictional grip for the` switch operatino shaft.

2lig. fl is asectional end elevation oi the relay, and

Fig. 5 is asectional sideelevation oit the Same.

Fig; 6 is a diagrammaticview illustrating the wiring. A

The diagrammatic plan in Fig. 6 of the drawings, illustrates a series oi machines A, equipped with the improvement, the ma- 'chines beingy operated by a common drive shaft l, the latter being geared to the shaft 2 oi: an electric motor 3.Y yThe motor 3 re ceives its current from the main Jreed wires e, 5, the said `iieed wires beingconnect-ed by means ot master switch 6 with the wires 7 and 8, the latter wire being connectedto a terminal of the motorr 3 via the resistance coil 9L Wire 7 leads to switch. B on or connected to the outermost machine. each machine being' provided with similar" switch in circuit with the motor, the switch on the machine nearest the motor having a Aterminal Aconnected with a resistance' coil 3.0,the latter in turn being in circuit through wire 7x with relay the relay being in circuit through wire 8X with a brake opera-tbeing connected through wire 11 with a"` terminal of `the motor 3l Each switch B may be ofany suitable construction. "ln Fig. l of the drawings we haveillustrated one ci the switchessecured to one of two bracket arms 12 rising from "the frame work of a mixing machine having iio between them inthe bosses 14 an oscillatory shaft 15 having anarin 16 in engagement with a projecting member 17 oi'E the switch. operating arm 18. in its position illustrated in Fig. 1, the member 17 rests upon arm 1,6 and thus serves to hold switch arm 18 in its uppermost position, and thus to `hold the switch closed. VBy imparting a of one of two rods 19 cachot which serves to connect two spaced arms 20; clamped upon the shaft 15.

To frictionallyhold the shaft 15, in any position to `which it may be moved, one.

or both of thebossesl 14 maybe provided withan enlarged recess 21-surroundingthe shaft 15, to receive an expanding washer 22 intermediate` the rings 23, the washer being expanded bythe pressure of a screw, the latter being threaded in tliefsaid boss and having athumb piece 24. For elevating the switch rod 18 to close the switch and return the contact member 17 inposition for engagement by arm 16, a lever 25 may be tulcrumed uponthe switch housingfto engage the inner end of contact member` 17., as

illustrated in Fig. 2.

The relay comprises a main casing C and asolenoid casingCX. In the main casing is mounted for vertical movement a Irod v25 whichcarries an insulating-block 26.

Secured upon the insulating block is a bridge piece 27 having at each end a contact piece 28. lhen the rod 25, is in its uppermost position the` contact pieces are heldin firnilcontactwith the terminal contacts e Z9 by a spring'29 surrounding the rod .belowI the insulating block 26 and supported upon a washer() held in position by a pin 31. The terminal Contact a has a reducedstem which passes throughan insiilating bushing 32 fitted in the coverD,

of the casing, `and its Aupper end is threadedv to receive suitable binding nutsvtor the wire SX leading' to the brakeandmotor assembly.

The terminal Contact has a stern threaded in the klower end orn an insulatingbushing 99 i the cover D and is .electrically connected with its bindingpost a* yforwire 7X,

through wire 34the solenoid in casing C", and .wire35. binding post a* being threaded inthe upper end of bushing 33 and a suitable insulating material being placed` intermediate the stem and post, asillustratedin F10'. 5.

,'lhe rodl 25 at its upper end Ais connected with a lever 36 fulcrumedat 37 upon `a post `38 rising from thecoverL D.4 A The fleverf 36,

in; turn,iis,operative1y connected with a rod,

connected with the solenoid core 40. The action of the solenoid is to normally hold the core 40 in the position shown in Fig, 5. However, when the circuit is broken by the openiiigoi, any one oi: the switches B, the rod 25 and contacts carried thereby will ital] by gravity and the core 40 willl be raised to such a height as not to be opera- 'ively ai'iected by the reenergizing of the solenoid winding by the closing of the open switch B. The arrangement is such that rod 25 mustbe manually lifted toagain move the core 4() toa position where.. the solenoid is again ,eifective to holdthe` contacts in engagement, and forsuch purpose we have shown a rod 41 oo nnectedto rod aty 40X and having aVV handle piecef41. VVThe. bracket armsr 12 of theswitch openving mechanisml .may 4be .made of a standard size, and the levers may be lowered orrfaised? .for different sized Almaclnnes. Toithisend the levers arepclainped within. ,sleeves' 42on shaft4 15, by means ,of thek set 'screws 1.43,

which permit vthe aforesaid ladjus'tm'ent. The arrangement of rods and levers .l9, '20 provides easy switch opening means Twithin the reach ofjrthe. operator .atvboth sides ofeach machine and throughout ,thelength of the latter. The relay is Adesigned ltofbe .installed at a. point, ydistant from,.theiria ,chine and under the control. of a responsible person in charge thereof.

Vln Athe claims the term ,driving connection. refines anyintermediary between'ithe .source .of power'and the machinedrive shaft, such, for ,exampleias themotor illustratedin the drawings, or. a .clutchibetween the motor. or any fdrivingdevice andlthe machine drive shaft.y i When a clutch is temployed it may be ofthe usual magnetic-,type maintained in engaged position by the ourrentl `and tree for' movement to v disengaged position by springs or other devicesupon .the

opening or thecircuit at the `switch. and, 'ref lay.- Suchclutch members are cominona'nd do not require further kdescription here.

Having tliusdesciibed `our invention what we. claimanddesire to protect by `Letters Paten-t is:

1. A safety switch having.stationary andI movable. contact v.I riembers,the flatter of which isA `normally held a way ,i`roin...ther `former by gravity, .means for sustaining movable contact inemben in` position against the stationary contact meinberincluding a` trip independent thereof, and manually V )perable means frictionallyaretained in any position to which .movedffor moving the trip to free the movable Contact member therefrom and to the` action,of

means for'autometlcelly meveigsaidnema gravity whereby the circuit may bequickly ber to open the circuit through the switch,`

an arm adapted to hold the Contact member against movement to open position, a shaft carrying said arm, and means Jfor turning said shaft including a lever lengthwise adjustably secured thereto andan operating rod Supported at one end of said lever and extending lengthwise cgt a machine to Which the switch may be applied, said lever `and arm extending in different radial directions relative to one another.

3. In devices of the character described, a switch comprising a contact member and means for automatically moving said memloer to open the circuit through the switch,

sm arm adapted to hold the contact member against movement to open position, a shaft carrying said armj and means Jfor turning said shaft 'from either side of a machine to which the switch may he applied, including spaced levers endwise adjnstably secured to and extending radially of Athe shaft and rods connecting said levers, said arm eX-v tending in a dilerent radial direction relative'to the radial direction of said levers.

Signed at Detroit, Michigan7 this 3rd day of May, 1918.

GEORGE GALPIN. DAVID H. BAER. 

